Consolidated Statements of Changes in Equity - USD ($) $ in Thousands	Total	Common stock	Contingent convertible preferred stock	Additional paid-in capital	Exchangeable shares of subsidiary	Retained earnings	Accumulated other comprehensive income	Treasury stock	Parent	Restricted stock units Restricted stock units
Beginning Balance at Dec. 31, 2013		$ 379	$ 14,446	$ 534,533	$ 1,958	$ 152,412	$ (9,361)	$ (534,957)		$ 117,258
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued		10		66,591
Contingent convertible preferred stock canceled or converted			0	0
Restricted stock units recognized, net of forfeitures										39,990
Restricted stock units delivered										(67,141)
Tax benefit (expense)				(4,661)		1,773
Exchangeable shares of subsidiary delivered					0
Dividends						(56,283)
Net income allocated to common stockholders	$ 43,388					43,388
Currency translation adjustment, net of tax	(8,608)						(8,608)
Repurchased								(36,179)
Ending Balance at Dec. 31, 2014		389	14,446	596,463	1,958	141,290	(17,969)	(571,136)	$ 255,548	90,107
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued		16		94,554
Contingent convertible preferred stock canceled or converted			(14,446)	14,446
Restricted stock units recognized, net of forfeitures										47,071
Restricted stock units delivered										(52,209)
Tax benefit (expense)				(7,856)		1,912
Exchangeable shares of subsidiary delivered					0
Dividends						(58,940)
Net income allocated to common stockholders	25,598					25,598
Currency translation adjustment, net of tax	(10,436)						(10,436)
Repurchased								(11,902)
Ending Balance at Dec. 31, 2015		405	0	697,607	1,958	109,860	(28,405)	(583,038)	283,356	84,969
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued		9		44,789
Contingent convertible preferred stock canceled or converted			0	0
Restricted stock units recognized, net of forfeitures										45,880
Restricted stock units delivered										(44,942)
Tax benefit (expense)				(7,668)		2,785
Exchangeable shares of subsidiary delivered					0
Dividends						(61,609)
Net income allocated to common stockholders	60,762					60,762
Currency translation adjustment, net of tax	$ (3,993)						(3,993)
Repurchased								(28,186)
Ending Balance at Dec. 31, 2016		$ 414	$ 0	$ 734,728	$ 1,958	$ 111,798	$ (32,398)	$ (611,224)	$ 291,183	$ 85,907